Bollettino valanghe

Central Sierra Nevada

Sierra Avalanche Center
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Pericolo valanghe

Tue
Alta quota
3 · Marcato
Limite del bosco
3 · Marcato
Sotto il limite
2 · Moderato
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Non aggiornato — questo bollettino è scaduto 5 years ago. Stai vedendo condizioni passate, non il bollettino in corso.

In sintesi

Strong ridgetop winds have drifted and deposited slabs of new snow (wind slabs) in lee areas in above treeline and near treeline terrain.  Isolated unstable slabs of new snow (storm slabs) may exist in wind protected areas below treeline. Any sun breaks that occur today could allow for warming instability to exacerbate the avalanche problems. CONSIDERABLE avalanche danger exists above treeline and near treeline with MODERATE avalanche danger below treeline.

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Likely
    Dimensione
    1–2

    Newly formed slabs of wind drifted snow are expected in lee areas above treeline and near treeline. The majority of wind slabs will be found mainly on NW-N-NE-E-SE aspects but may be encountered anywhere that wind drifted snow has deposited. Avalanche size up to D2 could occur today.

    Use clues such as blowing snow, cornice formations, wind pillows, and wind textured snow surfaces to identify slopes where unstable wind slabs may exist. Move around these slopes with an avoidance mindset. If breaks in cloud cover allow for strong sunshine to reach the snow surface, warming instability could make this avalanche problem easier to trigger.

  • Storm Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2

    Isolated unstable storm slabs may exist today in wind protected areas below treeline in the locations that have received the greatest amounts of new snow. Other areas may see more dry loose instability than storm slab instability. Avalanche size up to D2 is possible in the areas that have received the greatest amounts of new snow.

    Look for snow surface cracking while moving through untracked snow as a sign of potential storm slab instability. Exercise caution in steep terrain where either storm slab or dry loose avalanches could push a person into trees, rocks, etc. If breaks in cloud cover allow for strong sunshine to reach the snow surface, warming instability could make either storm slab or dry loose avalanche problems easier to trigger.

Avalanche Discussion

* The existing snowpack is in good condition to handle new snow loading. Any snowpack failures that occur today are expected to occur at or above the old/new snow interface.

* New snow has deposited on top of melt-freeze crust in areas of previous sun exposure, including some moderate slope angle northerly aspects.

Regioni coperte